HOLLOW NANOPARTICLES WITH HYBRID DOUBLE LAYERS

摘要

The present invention discloses the morphology of hollow, double-shelled submicrometer particles generated through a rapid aerosol-based process. The inner shell is an essentially hydrophobic carbon layer of nanoscale dimension (5-20 nm), and the outer shell is a hydrophilic silica layer of approximately 5-40 nm, with the shell thickness being a function of the particle size. The particles are synthesized by exploiting concepts of salt bridging to lock in a surfactant (CTAB) and carbon precursors together with iron species in the interior of a droplet. This deliberate negation of surfactant templating allows a silica shell to form extremely rapidly, sealing in the organic species in the particle interior. Subsequent pyrolysis results in a buildup of internal pressure, forcing carbonaceous species against the silica wall to form an inner shell of carbon. The incorporation of magnetic iron oxide into the shells opens up applications in external stimuli-responsive nanomaterials.

主权项

1. A method of producing hollow double shelled particles with an outer layer of ceramic, and an inner layer of carbon by an aerosol-based method, comprising the steps of:
a) preparing a precursor solution comprising (1) a ceramic source, (2) a carbon source, (3) an iron source, and (4) a surfactant; b) passing the precursor solution through a nozzle for atomization to form aerosol droplets; c) passing the aerosol droplets through a heating zone and a drying zone for evaporation, wherein the iron source binds with the surfactant in the interior of the droplet and the ceramic source is on the surface of the droplet; d) collecting the particles on a filter; and e) passing the particles for pyrolysis under the flow of an inert gas, wherein the carbon source located in the interior of the particle generates an inner layer from the inside of the particle.